Supercharged 302

[aharris]

OK, I need advice. Anybody here who runs a supercharger in their FFR.

I'm looking at a Kenne Bell unit for my 302 and as I'm going to rebuild the engine I'm thinking of running higher boost with low compression pistons. I want a daily driver thats fun and blows the doors off a slammed Honda.

I would welcome advice from any who have considered this option or have one installed. eg Does it fit under the hood, driveability, reliability, etc.

Thanks for the help.

Any opinions?

[superskippy]

My FFR is supercharged, however I would suggest using a vortech or a paxton. You will get a better response over at www.ffcobra.com, since that site caters to the FFR builders.

[MJN]

Andrew

I have a Kenne Bell set up on my 331 (302, 0.030" over, 1/4" stroke) and for all around performance I find it hard to beat. It does not have the top end HP potential of the centrifugals such as Paxton / Vortech but what it does have is a ton of torque at lower revs. If you want HP bragging rights bolt on a Vortech if you want the 'feel' of a big block without the weight / cost etc then I would recommend the Kenne Bell. With the fuel injection I can still get better than 20 mpg on a run and with 7 lbs of boost it still puts 400HP to the wheels.

[aharris]

Skippy

Thanks for the tip. Ill check it out..

Andrew

[aharris]

MJN

I'm really looking for across the range torque. This is why I want a KB. What other mods do you have to get the RWHP? I'm looking for suggestions before I plan the rebuild.

Andrew

[B. SMITH]

I AGREE WITH MJN. I AM ABOUT 400 HP BUT WITH THE KB YOU DON'T HAVE TO REV.
HUGE TORQUE AVAILABLE AT 1200 TO 4500 RPM. MAKES IT FEEL LIKE A BIG BLOCK AND EASY TO DRIVE. TREMENDOUS PULL IN 4TH GEAR FROM SLOW SPEEDS. EVEN 25 MPH. CENTRIFUGALS AREN'T LIKE THAT. HOPE THIS HELPS IN YOUR DECISION.

B. SMITH

[MJN]

Andrew

I had the Kenne Bell on an '89 Mustang for 50K miles before I used the Mustang as a donor for my FFR. Even on the stock 302 it was a lot of fun. The Mustang would run 113 MPH in the quarter with limited traction so in a FFR with a curb weight 1,000 lbs less it should run over 120 MPH trap speeds. That is a fun ride! I have not run my FFR at the track yet with the 331 but expect to once again be severely traction limited and hopefully closer to 130MPH. I'm still running the stock WC-T5 so I don't want to risk sticky tires to gain ET. Anyway my engine combination may be a little on the expensive side for what you are thinking but here's what I have. I bought my 331 kit from Probe in CA with a number of options including lightweight rods, steel crank and low compression forged pistons, with the machine work and me doing the assembly the short block cost me about $3000. I have TFS twisted wedge heads and the TFS stage 1 roller cam with Crane roller rockers. The Kenne Bell blower that I have is the smaller blower (1.5 liters) and will only push about 6.5 lbs of boost on my motor with the smallest pulley that Kenne Bell makes. I have been told by Jim Bell that the small blower is my limiting factor for HP at the moment and that with the 2.2 liter blower I should be able to raise the boost and tune for 100 or more HP. I have 42 lb injectors and a Pro-M 81mm mass air sensor. The throttle body is 70mm. The engine idles with a slight lope but pretty smoothly at 850 rpm and will pull from 1000 rpm in overdrive. 35 mph is comfortable in 5th gear with the slow 'blub blub blub' from the pipes. If you are going to rebuild I would recommend the lower compression pistons, I blew the head gaskets twice with the iron heads in the Mustang due to detonation but have been OK so far with the TFS. My compression worked out to 8.4:1 with a zero deck height and 61cc chambers. Overall for a 'driver' I find this set up ideal with the low weight of the FFR it really does have a lot of the feel of a much larger engine. The torque curve is fat and flat which sounds like what you're looking for but my motor is done at 5500 rpms with the small blower. So if you've made up your mind on a Kenne Bell, rebuild with dished forged pistons, beef up the bottom end with a stud girdle and go for the 2.2 liter blower set up. And, use the best head gaskets you can find. Good heads will help a bunch as always. Oh, and make sure that you have a fuel system that can keep up with the demands of the motor. The stock FF fuel lines are good enough as well as the factory fuel rails but a 255 lph pump in the tank and a second inline pump is a good idea.

Mike...

[MJN]

B Smith.

I only have 3.08 's in my car, yours with 3.73 's must really be a blast with the KB !

[Excaliber]

On the Excalibur Cobras the hood was modified with a "bubble" for clearance with a KB SC. Theres a pic of it in the Excalibur Owners Please Reply thread, pg 7 or so. Clearance could be an issue on other Cobras as well (with a KB). Therefore I was thinking Vortech because it will fit. But I ike the idea of a "true" blower with instantly available torque,,,,I hate to wait. LOL

Ernie

[MJN]

No hood clearance issues with a KB on the FFR. I even have a 1/2" phenolic spacer between the upper and lower intake to clear the higher rails on the TFS heads and there is still plenty of hood clearance.

[MJN]

Here's a picture of the KB on my FFR. No clearance issues anywhere just bolts straight on.

[aharris]

Mike

Nice....makes my mouth water.

Andrew

[Mr.Fixit]

Isn't that a cute little blower

[got snake?]

what are the pro's of a roots type blower vs Vortech's type?

GS

[MJN]

Technically the Kenne Bell is a Lysholm screw compressor it actually compresses the air in the blower case rather than just cramming it into the intake manifold like a roots blower. Because of this it is also more efficient than the roots, simplistically what that means is that it will heat the air less for a given boost and as we all know lower temps = denser air = more power. The roots and the Lysholm are both positive displacement superchargers. That is to say they move a fixed quantity of air per revolution no matter what the engine speed. That is why they are so good at providing boost and torque at low rpms. The centrifugals can also be very efficient depending on the design of the volute and the impellor, amongst other things, but they move air in a different way, more like a fan, and the boost increases exponentially with the impellor speed. So they provide little boost at low rpms but when they get spinning watch out because the boost can build in a hurry. One way around this excess boost issue with turbos is the use of a pop off valve that limits the boost. Both styles of blower (positive displacement / centrifugal)really need carefully sizing to the engine although the positive displacement blower is a lot more tolerant of over sizing than a centrifugal and will still be fun to drive even if it is too big for the engine. An oversized centrifugal or turbo isn't much fun, is very lazy at building boost, but when it does watch out. May be good for a track car but not so much fun on the street.

[SSSnake]

Speaking of the whipple chargers, the guy that is building my engine is working on a Studebaker Lark VIII. It originally had a 259 V8. Bored it and stroked it to 304 and put a whipple charger on it. 460 hp. and 500+ ft lbs of torque on dyno. Also has a toploader and ford 9 inch rear end. Man, what a sleeper.

Glenn

[MJN]

For those interested Whipple has a pretty good website www.whipplesuperchargers.com Kenne Bell has a site, www.kennebell.net which ismore a home 'page'. It has still to be updated with any decent information.